When I was a kid, there was one department store in town that had huge sales on Boxing Day. I think in reality they had a very limited number of big price items like washing machines that were massively reduced and then most of the stuff just with a little off, but that's besides the point.
I remember that people would actually go and camp outside from the morning of Christmas Eve, sit there all through Christmas, get people to bring them Christmas dinner, etc.
Always seemed completely crazy to me, I don't know if they are still doing it or not.